Lucy needs no additions! It's a name in its own right, and one I thought I'd use for my daughter, only she surprised me by looking less like a
Lucy than I'd have believed possible. But, I had a cat once who "had to be" given an L name so I chose
Lucinda and called her
Cindy; make of that what you will.
Lucille seems very whiney to me, also beige and drab, but there's always
Lucilla.